简单的登录跳转示例

olivee 4年前 ⋅ 1280 阅读

1. 建andriod项目

先打开andriod建一个项目,并创建一个空的activity emptyactivity.png

2. 配置layout

app\src\main\res\layout\activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">



    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="确认"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintRight_toLeftOf="parent"
        app:layout_constraintLeft_toRightOf="parent"/>

    <EditText
        android:id="@+id/password"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPassword"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="@+id/button"
        app:layout_constraintRight_toLeftOf="parent"
        app:layout_constraintLeft_toRightOf="parent"
        android:text=""
     />

    <TextView
        android:id="@+id/warning"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="@color/colorAccent"
        app:layout_constraintLeft_toLeftOf="@+id/password"
        app:layout_constraintTop_toBottomOf="@+id/password" />

</android.support.constraint.ConstraintLayout>

3. 编写MainActivity

package com.你自己的包名;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import java.util.Date;

public class MainActivity extends AppCompatActivity {

    EditText pwd;
    TextView warning;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
        warning = findViewById(R.id.warning);

        Button bt = findViewById(R.id.button);

        bt.setOnClickListener(
                new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String txt = pwd.getText().toString();
                String password = "123"; // 这里随便写个测试密码123
                if( txt.equals(password) ) {
                    Jump(v);
                } else {
                    warning.setText("密码错误");
                }
            }
        });

        pwd = findViewById(R.id.password);


    }

    public void Jump(View view){
        Intent intent = new Intent();
        intent.setClass(MainActivity.this, Main2Activity.class);
        startActivity(intent);
    }
}

建一个新的Main2Activity,代码部门省略